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      <td width="400px"><p class="toc level1"><a href="docinfo.html">Document Information</a></p>
<p class="toc level1 tocsp"><a href="gexaf.html">Preface</a></p>
<p class="toc level1 tocsp"><a href="gfirp.html">Part&nbsp;I&nbsp;Introduction</a></p>
<p class="toc level2"><a href="bnaaw.html">1.&nbsp;&nbsp;Overview</a></p>
<p class="toc level2"><a href="gfiud.html">2.&nbsp;&nbsp;Using the Tutorial Examples</a></p>
<p class="toc level1 tocsp"><a href="bnadp.html">Part&nbsp;II&nbsp;The Web Tier</a></p>
<p class="toc level2"><a href="bnadr.html">3.&nbsp;&nbsp;Getting Started with Web Applications</a></p>
<p class="toc level2"><a href="bnaph.html">4.&nbsp;&nbsp;JavaServer Faces Technology</a></p>
<p class="toc level2"><a href="giepx.html">5.&nbsp;&nbsp;Introduction to Facelets</a></p>
<p class="toc level2"><a href="gjddd.html">6.&nbsp;&nbsp;Expression Language</a></p>
<p class="toc level2"><a href="bnaqz.html">7.&nbsp;&nbsp;Using JavaServer Faces Technology in Web Pages</a></p>
<p class="toc level2"><a href="gjcut.html">8.&nbsp;&nbsp;Using Converters, Listeners, and Validators</a></p>
<p class="toc level3"><a href="bnast.html">Using the Standard Converters</a></p>
<p class="toc level4"><a href="bnast.html#bnasu">Converting a Component's Value</a></p>
<p class="toc level4"><a href="bnast.html#bnasv">Using <tt>DateTimeConverter</tt></a></p>
<p class="toc level4"><a href="bnast.html#bnasx">Using <tt>NumberConverter</tt></a></p>
<p class="toc level3 tocsp"><a href="bnasz.html">Registering Listeners on Components</a></p>
<p class="toc level4"><a href="bnasz.html#bnata">Registering a Value-Change Listener on a Component</a></p>
<p class="toc level4"><a href="bnasz.html#bnatb">Registering an Action Listener on a Component</a></p>
<p class="toc level3 tocsp"><a href="bnatc.html">Using the Standard Validators</a></p>
<p class="toc level4"><a href="bnatc.html#bnate">Validating a Component's Value</a></p>
<p class="toc level4"><a href="bnatc.html#bnatf">Using <tt>LongRangeValidator</tt></a></p>
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<p class="toc level3 tocsp"><a href="">Referencing a Managed Bean Method</a></p>
<p class="toc level4"><a href="#bnatp">Referencing a Method That Performs Navigation</a></p>
<p class="toc level4"><a href="#bnatq">Referencing a Method That Handles an Action Event</a></p>
<p class="toc level4"><a href="#bnatr">Referencing a Method That Performs Validation</a></p>
<p class="toc level4"><a href="#bnats">Referencing a Method That Handles a Value-Change Event</a></p>
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<p class="toc level2 tocsp"><a href="bnatx.html">9.&nbsp;&nbsp;Developing with JavaServer Faces Technology</a></p>
<p class="toc level2"><a href="gkmaa.html">10.&nbsp;&nbsp;JavaServer Faces Technology Advanced Concepts</a></p>
<p class="toc level2"><a href="bnawo.html">11.&nbsp;&nbsp;Configuring JavaServer Faces Applications</a></p>
<p class="toc level2"><a href="gkiow.html">12.&nbsp;&nbsp;Using Ajax with JavaServer Faces Technology</a></p>
<p class="toc level2"><a href="gkhxa.html">13.&nbsp;&nbsp;Advanced Composite Components</a></p>
<p class="toc level2"><a href="bnavg.html">14.&nbsp;&nbsp;Creating Custom UI Components</a></p>
<p class="toc level2"><a href="bnafd.html">15.&nbsp;&nbsp;Java Servlet Technology</a></p>
<p class="toc level2"><a href="bnaxu.html">16.&nbsp;&nbsp;Internationalizing and Localizing Web Applications</a></p>
<p class="toc level1 tocsp"><a href="bnayk.html">Part&nbsp;III&nbsp;Web Services</a></p>
<p class="toc level2"><a href="gijti.html">17.&nbsp;&nbsp;Introduction to Web Services</a></p>
<p class="toc level2"><a href="bnayl.html">18.&nbsp;&nbsp;Building Web Services with JAX-WS</a></p>
<p class="toc level2"><a href="giepu.html">19.&nbsp;&nbsp;Building RESTful Web Services with JAX-RS</a></p>
<p class="toc level2"><a href="gjjxe.html">20.&nbsp;&nbsp;Advanced JAX-RS Features</a></p>
<p class="toc level2"><a href="gkojl.html">21.&nbsp;&nbsp;Running the Advanced JAX-RS Example Application</a></p>
<p class="toc level1 tocsp"><a href="bnblr.html">Part&nbsp;IV&nbsp;Enterprise Beans</a></p>
<p class="toc level2"><a href="gijsz.html">22.&nbsp;&nbsp;Enterprise Beans</a></p>
<p class="toc level2"><a href="gijre.html">23.&nbsp;&nbsp;Getting Started with Enterprise Beans</a></p>
<p class="toc level2"><a href="gijrb.html">24.&nbsp;&nbsp;Running the Enterprise Bean Examples</a></p>
<p class="toc level2"><a href="bnbpk.html">25.&nbsp;&nbsp;A Message-Driven Bean Example</a></p>
<p class="toc level2"><a href="gkcqz.html">26.&nbsp;&nbsp;Using the Embedded Enterprise Bean Container</a></p>
<p class="toc level2"><a href="gkidz.html">27.&nbsp;&nbsp;Using Asynchronous Method Invocation in Session Beans</a></p>
<p class="toc level1 tocsp"><a href="gjbnr.html">Part&nbsp;V&nbsp;Contexts and Dependency Injection for the Java EE Platform</a></p>
<p class="toc level2"><a href="giwhb.html">28.&nbsp;&nbsp;Introduction to Contexts and Dependency Injection for the Java EE Platform</a></p>
<p class="toc level2"><a href="gjbls.html">29.&nbsp;&nbsp;Running the Basic Contexts and Dependency Injection Examples</a></p>
<p class="toc level2"><a href="gjehi.html">30.&nbsp;&nbsp;Contexts and Dependency Injection for the Java EE Platform: Advanced Topics</a></p>
<p class="toc level2"><a href="gkhre.html">31.&nbsp;&nbsp;Running the Advanced Contexts and Dependency Injection Examples</a></p>
<p class="toc level1 tocsp"><a href="bnbpy.html">Part&nbsp;VI&nbsp;Persistence</a></p>
<p class="toc level2"><a href="bnbpz.html">32.&nbsp;&nbsp;Introduction to the Java Persistence API</a></p>
<p class="toc level2"><a href="gijst.html">33.&nbsp;&nbsp;Running the Persistence Examples</a></p>
<p class="toc level2"><a href="bnbtg.html">34.&nbsp;&nbsp;The Java Persistence Query Language</a></p>
<p class="toc level2"><a href="gjitv.html">35.&nbsp;&nbsp;Using the Criteria API to Create Queries</a></p>
<p class="toc level2"><a href="gkjiq.html">36.&nbsp;&nbsp;Creating and Using String-Based Criteria Queries</a></p>
<p class="toc level2"><a href="gkjjf.html">37.&nbsp;&nbsp;Controlling Concurrent Access to Entity Data with Locking</a></p>
<p class="toc level2"><a href="gkjia.html">38.&nbsp;&nbsp;Improving the Performance of Java Persistence API Applications By Setting a Second-Level Cache</a></p>
<p class="toc level1 tocsp"><a href="gijrp.html">Part&nbsp;VII&nbsp;Security</a></p>
<p class="toc level2"><a href="bnbwj.html">39.&nbsp;&nbsp;Introduction to Security in the Java EE Platform</a></p>
<p class="toc level2"><a href="bncas.html">40.&nbsp;&nbsp;Getting Started Securing Web Applications</a></p>
<p class="toc level2"><a href="bnbyk.html">41.&nbsp;&nbsp;Getting Started Securing Enterprise Applications</a></p>
<p class="toc level1 tocsp"><a href="gijue.html">Part&nbsp;VIII&nbsp;Java EE Supporting Technologies</a></p>
<p class="toc level2"><a href="gijto.html">42.&nbsp;&nbsp;Introduction to Java EE Supporting Technologies</a></p>
<p class="toc level2"><a href="bncih.html">43.&nbsp;&nbsp;Transactions</a></p>
<p class="toc level2"><a href="bncjh.html">44.&nbsp;&nbsp;Resource Connections</a></p>
<p class="toc level2"><a href="bncdq.html">45.&nbsp;&nbsp;Java Message Service Concepts</a></p>
<p class="toc level2"><a href="bncgv.html">46.&nbsp;&nbsp;Java Message Service Examples</a></p>
<p class="toc level2"><a href="gkahp.html">47.&nbsp;&nbsp;Advanced Bean Validation Concepts and Examples</a></p>
<p class="toc level2"><a href="gkeed.html">48.&nbsp;&nbsp;Using Java EE Interceptors</a></p>
<p class="toc level1 tocsp"><a href="gkgjw.html">Part&nbsp;IX&nbsp;Case Studies</a></p>
<p class="toc level2"><a href="gkaee.html">49.&nbsp;&nbsp;Duke's Tutoring Case Study Example</a></p>
<p class="toc level1 tocsp"><a href="idx-1.html">Index</a></p>
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<a name="bnatn"></a><h2>Referencing a Managed Bean Method</h2>
<a name="indexterm-503"></a><a name="indexterm-504"></a><p><a name="indexterm-505"></a><a name="indexterm-506"></a>A component tag has a set of attributes for referencing managed bean methods
that can perform certain functions for the component associated with the tag. These
attributes are summarized in <a href="#bnato">Table&nbsp;8-5</a>.</p>

<a name="bnato"></a><p class="caption">Table&nbsp;8-5 Component Tag Attributes That Reference Managed Bean Methods</p><table><col width="23%"><col width="76%"><tr><th align="left" valign="top" scope="column"><p>Attribute</p>

</th>
<th align="left" valign="top" scope="column"><p>Function</p>

</th>
</tr>
<tr><td align="left" valign="top" scope="row"><p><a name="indexterm-507"></a><a name="indexterm-508"></a><tt>action</tt></p>

</td>
<td align="left" valign="top" scope="row"><p>Refers to a managed bean method that performs navigation
processing for the component and returns a logical outcome <tt>String</tt></p>

</td>
</tr>
<tr><td align="left" valign="top" scope="row"><p><a name="indexterm-509"></a><a name="indexterm-510"></a><tt>actionListener</tt><a name="indexterm-511"></a></p>

</td>
<td align="left" valign="top" scope="row"><p>Refers to a managed
bean method that handles action events</p>

</td>
</tr>
<tr><td align="left" valign="top" scope="row"><p><a name="indexterm-512"></a><a name="indexterm-513"></a><tt>validator</tt></p>

</td>
<td align="left" valign="top" scope="row"><p>Refers to a managed bean method that
performs validation on the component&rsquo;s value</p>

</td>
</tr>
<tr><td align="left" valign="top" scope="row"><p><a name="indexterm-514"></a><a name="indexterm-515"></a><tt>valueChangeListener</tt></p>

</td>
<td align="left" valign="top" scope="row"><p>Refers to a managed bean method that handles
value-change events</p>

</td>
</tr>
</table><p>Only components that implement <tt>ActionSource</tt> can use the <tt>action</tt> and <tt>actionListener</tt> attributes. Only components
that implement <tt>EditableValueHolder</tt> can use the <tt>validator</tt> or <tt>valueChangeListener</tt> attributes.</p>

<p><a name="indexterm-516"></a>The component tag refers to a managed bean method using a method expression
as a value of one of the attributes. The method referenced by an
attribute must follow a particular signature, which is defined by the tag attribute&rsquo;s
definition in the documentation at <a href="http://download.oracle.com/javaee/6/javaserverfaces/2.1/docs/vdldocs/jsp/">http://download.oracle.com/javaee/6/javaserverfaces/2.1/docs/vdldocs/jsp/</a>. For example, the definition of the <tt>validator</tt>
attribute of the <tt>inputText</tt> tag is the following:</p>

<pre>void validate(javax.faces.context.FacesContext,
     javax.faces.component.UIComponent, java.lang.Object)</pre><p>The following sections give examples of how to use the attributes.</p>



<a name="bnatp"></a><h3>Referencing a Method That Performs Navigation</h3>
<a name="indexterm-517"></a><a name="indexterm-518"></a><p><a name="indexterm-519"></a><a name="indexterm-520"></a>If your page includes a component, such as a button or a hyperlink,
that causes the application to navigate to another page when the component is
activated, the tag corresponding to this component must include an <tt>action</tt> attribute. This
attribute does one of the following:</p>


<ul><li><p>Specifies a logical outcome <tt>String</tt> that tells the application which page to access next</p>

</li>
<li><p>References a managed bean method that performs some processing and returns a logical outcome <tt>String</tt></p>

</li></ul>
<p>The following example shows how to reference a navigation method:</p>

<pre>&lt;h:commandButton
    value="#{bundle.Submit}"
    action="#{cashier.submit}" /></pre>

<a name="bnatq"></a><h3>Referencing a Method That Handles an Action Event</h3>
<a name="indexterm-521"></a><a name="indexterm-522"></a><p><a name="indexterm-523"></a><a name="indexterm-524"></a><a name="indexterm-525"></a>If a component on your page generates an action event, and if that
event is handled by a managed bean method, you refer to the method
by using the component&rsquo;s <tt>actionListener</tt> attribute.</p>

<p>The following example shows how the method is referenced:</p>

<pre>&lt;h:commandLink id="NAmerica" action="bookstore"
     actionListener="#{localeBean.chooseLocaleFromLink}"></pre><p>The <tt>actionListener</tt> attribute of this component tag references the <tt>chooseLocaleFromLink</tt> method using a method
expression. The <tt>chooseLocaleFromLink</tt> method handles the event when the user clicks the hyperlink
rendered by this component.</p>



<a name="bnatr"></a><h3>Referencing a Method That Performs Validation</h3>
<a name="indexterm-526"></a><a name="indexterm-527"></a><p><a name="indexterm-528"></a><a name="indexterm-529"></a>If the input of one of the components on your page is validated
by a managed bean method, refer to the method from the component&rsquo;s tag
by using the <tt>validator</tt> attribute.</p>

<p>The following example shows how to reference a method that performs validation on
<tt>email</tt>, an input component: </p>

<pre>&lt;h:inputText id="email" value="#{checkoutFormBean.email}"
    size="25" maxlength="125"
    validator="#{checkoutFormBean.validateEmail}"/></pre>

<a name="bnats"></a><h3>Referencing a Method That Handles a Value-Change Event</h3>
<a name="indexterm-530"></a><a name="indexterm-531"></a><p><a name="indexterm-532"></a><a name="indexterm-533"></a><a name="indexterm-534"></a>If you want a component on your page to generate a value-change event
and you want that event to be handled by a managed bean method,
you refer to the method by using the component&rsquo;s <tt>valueChangeListener</tt> attribute.</p>

<p>The following example shows how a component references a <tt>ValueChangeListener</tt> implementation that
handles the event when a user enters a name in the <tt>name</tt> input
field:</p>

<pre>&lt;h:inputText
     id="name"
     size="50"
     value="#{cashier.name}"
     required="true">
    &lt;f:valueChangeListener type="listeners.NameChanged" />
&lt;/h:inputText></pre><p>To refer to this managed bean method, the tag uses the <tt>valueChangeListener</tt>
attribute:</p>

<pre>&lt;h:inputText
     id="name"
     size="50"
     value="#{cashier.name}"
     required="true"
     valueChangeListener="#{cashier.processValueChange}" />
&lt;/h:inputText></pre><p>The <tt>valueChangeListener</tt> attribute of this component tag references the <tt>processValueChange</tt> method of <tt>CashierBean</tt>
by using a method expression. The <tt>processValueChange</tt> method handles the event of
a user entering a name in the input field rendered by this component.</p>


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